Overhead crane frame or bridge



1961 w. s. CHAPlN, JR., ET Al. 2,997,005

OVERHEAD CRANE FRAME OR BRIDGE 4 Sheets-Sheet 1 Filed Jan. 20, 1960 JHIEHJUPE William S. (la/in In E r/Laral I! .5122 1. n6

g- 1961 w. s. CHAPIN, JR ETAI. 2,997,005

OVERHEAD CRANE FRAME OR BRIDGE Filed Jan. 20, 1960 4 Sheets-Sheet 2fnyenfar's Mil 1 11am .5. Cfie a'n J'r: Erhard H Steins ZMNW l 5.

Aug. 22, 1961 w. s. CHAPIN, JR.. ETAI. 2,997,005

OVERHEAD CRANE FRAME OR BRIDGE Filed Jan. 20, 1960 4 Sheets-Sheet 3William iffla n'n Jr Erhard H. Steins 1961 w. s. CHAPIN, JR ET Al.2,997,005

OVERHEAD CRANE FRAME OR BRIDGE 4 Sheets-Sheet 4 Filed Jan. 20, 1960 KW ia I h I I H H H H I I I M WM Wm fZYZ E'HZUFE W/lt'am 5 (kqaz'n In Erhardf1. Steins 2,997,005 OVERHEAD CRANE FRAME OR BRIDGE William S. Chapin,Jr., Spring Lake Township, Muskegon County, and Erhard H. Steins, NortonTownship, Muskegon County, Mich., assignors to Manning, Maxwell & MooreIncorporated, Muskegon, Mich., a corporation of New Jersey Filed Jan.20, 1960, Ser. No. 3,593 10 Claims. (Cl. 105-163) This invention relatesto improvements in overhead crane frames or bridges, and moreparticularly to the main bridge or frame construction for overheadcranes of the heavy duty type, the invention being particularlydesirable for use in connection with cranes of the type of ladle cranes,wherein there are separate trolleys carrying separate hoisting meanssupported entirely by the crane bridge which is in itself a trolleycarrying the full load on the hoisting mechanisms as well as the load ofthe crane itself, although the invention will have other uses andpurposes as will be apparent to one skilled in the art.

Overhead cranes, particularly those of the larger type, most commonlyembody a bridge supported on trucks movable along tracks carried byrunway beams supported on columns which may be independent of, attachedto, or integral with the building columns. This main frame supports theentire weight of the overhead crane plus all the loads that may beconnected to the hoisting means associated therewith. Some overheadcranes, particularly ladle cranes of the type used in foundries for thepouring and transporting of molten metal, ingots, castings, and thelike, embody dual trolleys each equipped with hoisting apparatus. Such acrane would embody a main frame having opposed parallel end tie members,a pair of main girders therebetween to support track means for thetrolley carrying the main hoist, and a secondary pair of girders betweenthe end tie members having track means for supporting the trolleycarrying the lighter load hoist mechanism. When it is considered thatthe load upon the main hoist trolley may exceed 200 tons, while thatupon the auxiliary trolley may run between and 50 tons, it will beapparent at once that there is considerable stress on the frame and thedeflection of the secondary girders is not the same as the deflection ofthe main griders.

Heretofore, all girders and end tie members have been connected rigidlytogether by bolting, riveting, welding, or in an equivalent manner,whereby the main frame was a single rigid structure. Consequently,deflection in the secondary girders, differing from that in the maingirders, caused a tremendous load on the rigid connections between thesecondary girders and the end tie members. Such deflection causes theends of the secondary girders to tend to assume a slightly angularposition relatively to the end tie members, and the tie members areprevented from assuming any slightly angular position by means of therigid connections with the main girders. The unfortunate result was thatfailures occurred at the connections between the secondary girders andthe end tie members.

Since the end tie members are held in upright position solely by therigid connections with the main girders, such problem did not exist withcranes having only one pair of girders connected to the end tie members,because those end tie members were free to assume the same angularity asthat of the ends of the main girders, but the difficulty of stressconcentration resulting in failures occurred when more than one pair ofgirders were rigidly connected to the end tie members.

Accordingly, it is an important object of this invention to provide amain frame or bridge for an overhead rates atent Patented Aug. 22, 1961crane that overcomes the objections above noted to the structureutilized heretofore.

It is another important object of this invention to provide an overheadcrane having a main frame or bridge with two pair of girders connectedto end tie members, one pair being rigidly connected to the end tiemembers, and an articulate connection being provided between the ends ofthe other pair of girders and the end tie members,

It is also an object of this invention to provide an overhead cranehaving a main frame embodying more than one pair of girders connected tothe end tie members, one pair of the girders being rigidly connected tothe tie members, while the remaining girders are connected to the endtie members in a manner to permit relative movement between the girderends and the tie members.

Still another feature of the invention resides in the provision of anoverhead crane having a main frame embodying end tie members and aplurality of girders extending between and transversely to the end tiemembers, there being an articulate connection between the ends of atleast some of the girders and the end tie members.

It is also an object of this invention to provide an overhead cranehaving a main frame with a pair of load supporting girders connectedrigidly to the end tie members, and another pair of girders forsupporting a load of a different amount connected to the end tic membersin a manner to permit relative pivotal movement of the girders withrespect to the end tie members.

Also a feature of this invention is the provision of an overhead cranehaving a main frame in which channel brackets are provided on the endtie members, and at least one pair of girders extending between thoseend tie members are seated within the channel brackets, there beingmeans extending across the brackets beneath the girder ends to supportthe girders.

While some of the more salient features, characteristics and advantagesof the instant invention have been above pointed out, others will becomeapparent from the following disclosures, taken in conjunction with theaccompanying drawings, in Which FIGURE 1 is a fragmentary sideelevational view of an overhead crane embodying principles of theinstant invention, with parts broken away and parts shown in section;

FIGURE 2 is a fragmentary end view of the structure seen in FIGURE 1,taken from the righthand side of FIGURE 1;

FIGURE 3 is a diagrammatic top plan view of the main frame structure ofthe crane, with all parts thereabove removed for purposes of clarity;

FIGURE 4 is an enlarged fragmentary end view of the main frame, someparts being shown diagrammatically;

FIGURE 5 is an enlarged fragmentary vertical sectional view, takensubstantially as seen by the line VV of FIGURE 3, looking in thedirection of the arrows;

FIGURE 6 is a reduced fragmentary vertical sectional view, takensubstantially in the same location as FIGURE will also be appreciatedthat where reference is made to end tie members, girders, and the like,these are not usually formed of one piece of material, but arefabricated of metal plates and slabs, riveted, bolted, or weldedtogether in a known manner to provide a girder or the like of suitablesize and strength for the intended purpose, and the fabrication of allof the parts of such girders will not be herein specifically set forth.

The illustrated embodiment of the overhead crane embodies a bridge .ormain frame, generally indicated by numeral 1, which carries the entirecrane load. Each corner of the main frame 1 is supported by a truck 2having a plurality of wheels 3 thereon, in the illustrated instancethere being four such wheels on each of the four trucks. The trucks aredesigned to move on track rails 4-4 which may be supported, asdiagrammatically indicated at 5--5 in FIGURE 1, on runway beamssupported on columns which may be independent of, attached to, orintegral with the building columns.

It will therefore be apparent that the bridge with the trucks 2constitutes an immense trolley, and carried by suitable framework of aknown type, suspended from this trolley, is a suitable control room 6 asseen in FIG- URE 2, a number of flights of stairs 7, various platformsas indicated at 8, catwalks as indicated at 9, upstanding handrails at10, lights 11, as well as all of the various motors and equipmentnecessary to operate the entire crane structure.

Ridable upon a track formed by rails 1212 carried by portions of themain frame 1 to be later described, is a light capacity trolley 13. Thistrolley 13 carries suitable motors and hoisting mechanism,diagrammatically indicated at 14 and 15, from which a pair of load hooks16 and 17 depend on suitable chains or ropes. These hooks are forrelatively light loads, and by way of example and not by way oflimitation, the hook 16 might carry a load of 40 tons while the hook 17would pick up a load of approximately 5 tons.

At a higher level on the main frame 1 is another wider track formed byrails 18-18 on which a heavy capacity trolley 19 may travel. Thistrolley carries suitable heavy duty motors 202tl and hoisting drums 2121from each of which a hook 22 depends on suitable lifting chains orropes, one of these hooks being seen in FIG- URE 1. When the crane isused to handle ladles of molten metal, the two hooks 22 take a ladlefrom opposite sides and carry it along to the pouring location, when oneof the smaller hooks on the trolley 13 may be utilized to tip the ladleand pour at the proper location. This higher trolley 19 may carry a loadreaching into several hundred tons.

Now with reference more particularly to FIGURES 3, 4 and 5, it will beseen that the frame 1 comprises a pair of opposed parallel and like endtie members 2323 each of which is connected with one of the aforesaidtrucks 2 at each end thereof. These end tie members 2323 are in the formof large heavy fabricated beams, but for purposes of convenience hereinwill be referred to as they are in manufacturing practice as end tiemembers.

Extending between and transversely to the end tie members 23-43 is apair of spaced main girders 24-24. These girders support the rails 18-18forming the track for the upper heavy capacity trolley 19. The two maingirders 2424 are rigidly secured to the end tie members as by belts orrivets 25 seen in FIGURE 4. The end tie members 23-23 are maintained inupright position by this rigid securement thereto of the ends of themain girders 2 3-24. Consequently, any deflection of the main girders2424 due to the load thereon will cause no trouble, since the end ties23-23 may tip from the vertical and follow along with such deflection.

However, in the present instance, for carrying the tracks formed byrails 1212 for the light capacity trolley 13, secondary girders 2626 areprovided. Should these girders 2626 be rigidly connected to the end ties23-23 as well as the main girders 24-24, failure would possibly occur atthe connections between the ends of the secondary girders and the endtie members. This would be due to the fact that the secondary girderscarry a different load than the main girders and are therefore subjectto different conditions of possible deflection. But the end tie membersbeing held by the main girders cannot respond to a deflection of thesecondary girders because they are prevented from so doing by the maingirders. Assuming, for example with rigid connections between thesecondary girders and the end ties, that the secondary girders arecarrying a full load while the main girders are carrying substantiallyno load, the secondary girders have a tendency for the end portionsthereof to assume a slight angle with respect to the end tie members,thereby setting up a terrific concentration of stresses at theconnections with the end tie members. In the past, failures frequentlyresulted at those connection points.

To overcome such a situation, the instant invention provides What mayconveniently be termed an articulate connection between each end of eachsecondary girder and the respective end tie mmber; i.e., a connectionthat permits a relative movement between the end of a secondary girderand the end tie membr, thereby permitting the secondary girders todeflect under load, and no additional stress is applied to theconnections between the secondary girders and end tie members regardlessof what load may be on the main girders.

Various forms of articulate connections between the secondary girdersand the end tie members may be utilized, two modifications being setforth herein. The first and preferred form of such connection is bestseen in FIG- URES 3 and 5. As stated above, the secondary girders 26-26are at a lower level with respect to the end tie members than the maingirders 2424. To accomplish this, the end tie members are each providedwith a recess 27 therein as best seen in FIGURE 3, and the secondarygirders are secured to the end tie members adjacent the bottom of thatrecess, whereby the rails 1212 may extend beyond the secondary girdersinto the recess of the end tie members.

Adjacent each end of each secondary girder, the respective end tiemember has secured thereto a channel shaped bracket 28, the base ofwhich is rigidly affixed to the end tie member, and the arms of whichextend parallel with the secondary girder. Each arm is provided withreinforcing wings as indicated at 29 on the outer sides thereof. The endof the secondary girder extends between the arms of a bracket, andthrough the bracket arms and girder end a pivot pin 30 is mounted, thispin being held in position by a key 31 secured to one of the bracketarms. The pivot pin supports the end of the secondary girder, and as asafety factor, a shelf 32 is preferably provided between the arms of thebracket a slight distance below the bottom of the end of the secondarybeam, as seen best in FIGURE 5. Such shelf will support the end of thesecondary girder in the event of failure of the pivot pin for anyreason.

It will be seen, therefore, that the pivot pins supporting the ends ofthe secondary girders readily permit a deflection of those girders and atipping of the ends of the girders relatively to the end tie memberswithout any additional stress being imposed upon the connection betweenthe secondary girders and end tie members. Consequently, there should beno failures at the points of connection regardless of the differentloads carried by the trolleys on the main and secondary girders.

In FIGURES 6 and 7, we have illustrated a different form of articulateconnection between the end of a secondary girder and an end tie member.In this instance, a bracket 33 is secured to the end tie member 23, thisbracket being of channel shape but having a bottom 34 between the armsthereof, with suitable bracing ribs 35 underneath the bottom. The end ofa secondary girder 26 merely seats in the socket formed by the bracketand ass'aoos rests upon the cross member or bottom 34, no securing meansbeing utilized. Since the end tie members are held in proper spacing bythe main girders 24-24, there is no opportunity for the secondarygirders to slip out of the socket brackets 33. Resting upon the bracketbottom or shelf 34, each secondary girder is free to assume a slightdeflection, with the tendency of the girder end to be disposed at aslight angle to the vertical wall of the end tie member. No additionalstress will be imposed on the connection between the secondary girderand the end tie member regardless of the relative loads carried by thetrolleys 13 and 19.

From the foregoing, it will be apparent that we have provided anoverhead crane having an excess of one pair of girders extending betweenthe end tie members of the main frame, and yet there is no additional orundue stress imposed upon the connections between the ends of thegirders and the end tie members, by virtue of the articulate connectionssupplied between all but the main girders and the end tie members. Theconstruction is extremely long lived, highly durable, and eliminates thepossibility of failures to a considerable extent.

It will be understood that modifications and variations may be eifectedwithout departing from the scope of the novel concepts of the presentinvention.

We claim as our invention:

1. In the bridge or main frame for an overhead crane, a pair of opposedparallel end tie members, a pair of main girders between said end tiemembers and with their ends rigidly connected to said end tie members, apair of secondary girders between said end tie members, and anarticulated connection between the respective end tie member and eachend of said secondary girders.

2. In the main frame for a heavy duty overhead crane, a pair of parallelend tie members, a pair of load bearing main girders between said endtie members, a pair of load bearing secondary girders between said endtie members, a connection at each end of one of said pairs of loadbearing girders and the respective end tie members permitting relativemovement therebetween, and the other pair of load bearing girders beingrigidly connected to the end tie members.

3. In the main frame of an overhead crane, a pair of opposed parallelend tie members, a plurality of pairs of load bearing girders extendingbetween and transversely to said end tie members, articulated connectingmeans between the end tie members and certain of said pairs of loadbearing girders, and the remaining load bearing girders being rigidlyconnected to said end tie members.

4. In the main frame of an overhead crane, a pair of opposed parallelend tie members, a pair of main girders extending between andtransversely to said end tie members and with the ends thereof rigidlysecured to the respective end tie members, track means on said girdersto support a heavy load bearing trolley, a pair of secondary girdersextending between and transversely to said end tie members, connectingmeans between the ends of said secondary girders and the respective endtie members permitting relative pivotal movement between the girder endsand the end tie members, and track means on said secondary girders tosupport a lesser load bearing trolley.

5. In the main frame of an overhead crane, end tie members, a pair ofmain girders extending between and transversely to said end tie membersand having their ends rigidly connected to said end tie members, a pairof secondary girders extending between and transversely to said end tiemembers, a bracket on said end tie members adjacent each end of thesecondary girders, and means pivotally connecting the ends of saidsecondary girders to said brackets.

6. In the main frame of an overhead crane, end tie 6 members, a pair ofmain girders extending between and transversely to said end tie membersand having their ends rigidly connected to said end tie members, a pairof secondary girders extending between and transversely to said end tiemembers, a channel shaped bracket on said end tie members adjacent eachend of said secondary girders, and each end of said secondary girdersbeing disposed in the channel of one of said brackets to permit relativemovement between the ends of the secondary girders and said end tiemembers.

7. In the main frame of an overhead crane, end tie members, a pair ofmain girders extending between and transversely to said end tie membersand having their ends rigidly connected to said end tie members, a pairof secondary girders extending between and transversely to said end tiemembers, brackets on said end tie members adjacent the ends of saidsecondary girders, spaced arms on each bracket extending perpendicularto said end tie members, each end of a secondary girder being disposedbetween the arms of a bracket for pivotal movement relatively thereto,and a cross member between the arms of each bracket beneath therespective end of a secondary girder.

8. In the main frame of an overhead crane, end tie members, a pair ofmain girders extending between and transversely to said end tie membersand having their ends rigidly connected to said end tie members, a pairof secondary girders extending between and transversely to said end tiemembers, brackets on said end tie members adjacent the ends of saidsecondary girders, spaced arms on each bracket extending perpendicularto said end tie members, a cross member between the arms of each saidbracket, and each end of a secondary girder resting loosely on a bracketcross member between the bracket arms and spaced from the respective endtie member.

9. In the main frame of an overhead crane, end tie members, a pair ofmain girders extending between and tranversely to said end tie membersand having their ends rigidly connected to said end tie members, a pairof secondary girders extending between and tranversely to said end tiemembers, brackets on said end tie members adjacent the ends of saidsecondary girders, spaced arms on each bracket extending perpendicularto said end tie members, each end of a secondary girder being disposedbe tween the arms of a bracket and spaced from the respective end tiemember, and a pivot pin passing through the bracket arms and girder endtherebetween.

10. In the main frame of an overhead crane, end tie members, a pair ofmain girders extending between and transversely to said end tie membersand having their ends rigidly connected to said end tie members, a pairof secondary girders extending between and transversely to said end tiemembers, brackets on said end tie mem bers adjacent the ends of saidsecondary girders, spaced arms on each bracket extending perpendicularto said end tie members, each end of a secondary girder being disposedbetween the arms of a bracket and spaced from the respective end tiemember, a pivot pin passing through the bracket arms and girder endtherebetween, and a lateral shelf between the arms on each bracket belowthe end of the respective secondary girder to support the same in theevent of failure of the pivot pin.

References Cited in the file of this patent UNITED STATES PATENTS Re.22,905 Scheyer Aug. 12, 1947 495,783 Cavallaro Apr. 18, 1893 944,054Sawyer Dec. 21, 1909 1,662,197 Macomber Mar. 13, 1928 1,662,768 WaitMar. 13, 1928 2,260,317 Harry Oct. 28, 1941

